METABOLISM PATHWAYS OF RBC

Question 1

major source of red cell energy

Answer 1

Emden-Meyerhof Pathway

Question 2

Emden-Meyerhof Pathway yields

Answer 2

2 ATPs

Question 3

ATP controls and prevents

Answer 3

controls Na and K ; prevent oxidation of membrane lipid

Question 4

responsible for generation of 2,3-BPG

Answer 4

Rapoport-Leubering Pathway

Question 5

regulates hemoglobin affinity of oxygen

Answer 5

2,3-BPG

Question 6

a shunt pathway to glycolysis which is operative in the erythrocytes of man and other mammals

Answer 6

Rapoport-Leubering Pathway

Question 7

mainly concerned with the synthesis of 2,3 - BPG in the RBC

Answer 7

Rapoport-Leubering Pathway

Question 8

1,3-BPG produced in glycolysis is converted to 2,3-BPG by the enzyme __

Answer 8

2,3-BPG Mutase

Question 9

2,3-BPG is hydrolyzed to 3-phosphoglycerate by __

Answer 9

bpg phosphatase

Question 10

about ___ of the glucose that gets coverted to ____ in erythrocytes goes via ____

Answer 10

about 15-20% of the glucose that gets converted to lactate in erythrocytes goes via 2,3-BPG synthesis

Question 11

significance of 2,3-BPG

Answer 11

1. combines with hemoglobin and reduces the affinity towards oxygen
2. in the presence of 2,3 BPG, oxyhemoglobin will unload oxygen more easily in tissues.
3. Under hypoxic conditions the 2,3-BPG concentration in the RBC increases, thus favoring the release of oxygen to the tissues even when PO2 is low.

Question 12

a metabolic pathway parallel to glycolysis.

Answer 12

pentose phosphate pathway /hexose monophosphate shunt

Question 13

pentose phosphate pathway /hexose monophosphate shunt generates

Answer 13

generates NADPH and pentoses (5-carbon sugars) as well as ribose 5-phosphate, the last one a precursor for the synthesis of nucleotides

Question 14

___% of glycolysis occurs in the pentose phosphate pathway /hexose monophosphate
shunt and an aerobic pathway

Answer 14

10% glycolysis occurs in this pathway

Question 15

pentose phosphate pathway Provides reduced glutathione to prevent

Answer 15

Provides reduced glutathione to prevent hemoglobin denaturation

Question 16

in pentose phosphate pathway, G6PD deficiency yields

Answer 16

G6PD deficiency yields Heinz bodies

Question 17

other names of pentose phosphate pathway

Answer 17

Hexose monophosphate Pathway
HMP Shunt
Phosphogluconate Pathway

Question 18

alternative route for the metabolism of glucose
more complex pathway than glycolysis
more anabolic in nature

Answer 18

HMP shunt

Question 19

HMP shunt takes place in ___

Answer 19

Cytosol

Question 20

tissues highly active in HMP shunt

Answer 20

Liver, Adipose Tissue, Adrenal Gland, Erythrocytes, Testes and Lactating Mammary Gland.

Question 21

HMP shunt is concerned with the biosynthesis of __

Answer 21

NADPH and pentoses

Question 22

importance of NADPH

Answer 22

1. used in the synthesis of certain aminoacids involving the enzyme glutamate dehydrogenase
2. used for the biosynthesis of fatty acids and steroids
3. keeps the glutathione of RBC in reduced state to preserve the integrity of RBC membrane

Question 23

Maintains hemoglobin in Ferrous state to be functional

Answer 23

Methemoglobin reductase pathway

Question 24

BREAKDOWN OF RED BLOOD CELLS

Answer 24

As RBC cells age: decrease enzymes, ATP, size and increase density

Question 25

destruction of senescent red cells by spleen

Answer 25

culling

Question 26

BREAKDOWN OF RED BLOOD CELLS PATHWAYS

Answer 26

Extravascular
Intravascular